Finding sincerity

Sincerity is an important attitude that a human being should have because it shows one's honesty and respect to others. How can we identify if the person is sincere in everything he say, is it a an assurance that a person is sincere whenever he say flowering words? what do you think?
For me, I think it is not an assurance that a person is sincere in everything he say because according to the saying, "action speaks louder than voice". It is important to show what we wanted and emphasize it through action so that others should believe and give their trust on us.
Some people don't give their full trust to others unless they saw a proof that the person is trustworthy. I myself, I don't easily give my 100% trust to others because trust for me is a sacred thing that should be given a great value.

@-_kristinepili_-@